added experience tracking and automatic role assigning at given levels

includes: set role command to set a role to a given level (it clears out previous levels)
automatic level config generation on startup
min/max/multiplier configuration
job to persist the xp of the previous minute
added delayed scheduler start, so that events have a discord context in order to function
added role listener to automatically add and mark roles when they are created/deleted
fixed user in a server not being created correctly
added role service to give users role given by id
added server reference to role

abstracto-application/executable/pom.xml

@@ -63,6 +63,12 @@
             <version>${project.version}</version>
         </dependency>
 
+        <dependency>
+            <groupId>dev.sheldan.abstracto.modules</groupId>
+            <artifactId>experience-tracking-impl</artifactId>
+            <version>${project.version}</version>
+        </dependency>
+
         <dependency>
             <groupId>dev.sheldan.abstracto.scheduling</groupId>
             <artifactId>scheduling-impl</artifactId>